What effect may prolonged high humidity levels have on atmospheric conditions?

Prolonged high humidity levels significantly influence atmospheric conditions by increasing the heat index. The heat index represents the perceived temperature that combines air temperature and relative humidity to indicate how hot it feels to the human body. When humidity is high, sweat does not evaporate as readily, preventing the body from cooling down effectively. This can lead to a higher apparent temperature, making hot weather feel even more oppressive and increasing the risk of heat-related illnesses.

Understanding the impact of humidity on the heat index is essential for assessing weather conditions, particularly in warm climates. High humidity can also influence other weather patterns, but the direct relationship between humidity and the perception of heat is crucial for human health and safety.